Objectives
 - Streams
 - Files
 
STREAMS

Most common named streams:
∙ stdout
∙ stderr
∙ stdin (input from keyboard or | from another program)

$ ls
_NOTES.txt  a.c

# That output ↑ was on stdout.

$ ls  >  file_list.txt
_NOTES.txt  a.c

# '> file_list.txt' redirects stdout (but not stderr) to the file file_list.txt.

$ ls *.java
ls: cannot access '*.java': No such file or directory

# That output ↑ was on stderr.

$ ls *.java  >  file_list_java.txt
ls: cannot access '*.java': No such file or directory

# The error message was not redirected.   (You could have used '2> file_list_java.txt.)

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"EVERYTHING* IS JUST BYTES"
 * on computer, phone, network, screen (maybe elsewhere)

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How to view contents of a file.

$ xxd  -g1  c.txt
00000000: 41 42 43 0a          ABC.

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Where to find information on parameters to these functions.

- Reference sheet

- From bash:
  $  man fopen

  $  man fputc

  $  man fclose
 
- From Vim:
  Put your cursor over the function name and press shift-k  (capital K).

Press q to exit the man page viewer.